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2021 Polestar 2 Intermittent No-Start Condition - Completely Dead

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Mike T. · rep 0 · May 25, 5:20 AM · 1 replies · solved · Question

Vehicle: 2021 Polestar 2 Long Range Dual Motor

Hi everyone,

I'm having a really frustrating problem with my 2021 Polestar 2 Long Range Dual Motor. About once a week, I'll get in the car, press the brake, and nothing happens. It's completely dead – no lights, no infotainment, no response whatsoever. It's like the 12V battery is completely flat, but then after 10-30 minutes of waiting, or sometimes just trying again later, it suddenly comes back to life and starts normally.

There are no warning lights when it does start, and no error messages. I've had the 12V battery checked, and they said it was fine, but this intermittent nature is driving me crazy. Could it be a faulty relay, a software issue, or something else entirely?

Any Polestar 2 owners experienced this phantom no-start condition? It's making me nervous to rely on the car.

✓ Accepted solution

ClearTheCode Admin

ClearTheCode Team · rep 0 · May 25, 5:20 AM

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ClearTheCode admin answer:

An intermittent 'completely dead' no-start condition on your 2021 Polestar 2, especially when the 12V battery tests fine, points to a tricky diagnostic problem. In EVs, the 12V battery powers all the low-voltage systems, including the computers that 'wake up' the car and engage the high-voltage system for driving. When it goes completely dead, it often indicates a power delivery or control issue.

Here are potential causes and diagnostic considerations:

  1. Intermittent 12V Battery Fault: Even if it tested 'fine' once, an aging 12V battery can have intermittent internal shorts or capacity issues that only manifest under certain conditions. A load test over time might reveal weakness. This is a very common cause of EV no-starts.
  2. Battery Management System (BMS) or Body Control Module (BCM) Glitch: These modules control power distribution and vehicle wake-up sequences. An intermittent fault in either could prevent the car from powering up correctly.
  3. Main Contactor/Relay Issue: The main high-voltage contactor connects the high-voltage battery to the rest of the drivetrain. While it's a high-voltage component, its activation is controlled by the 12V system. An intermittent fault in the contactor or its control relay could prevent the car from 'starting'.
  4. Key Fob Battery/Antenna: While less likely to cause a 'completely dead' state, a weak key fob battery or an issue with the car's keyless entry antenna could prevent the car from recognizing the key and initiating the start sequence.
  5. Loose or Corroded Connections: Check the 12V battery terminals for any looseness or corrosion. Also, inspect the main grounding points for the vehicle's electrical system.

When to see a shop:

  • Don't Delay: An intermittent no-start is unreliable and can leave you stranded. Schedule service with a Polestar dealership or a qualified EV specialist.
  • Advanced Diagnostics: Polestar service centers have specialized diagnostic tools that can read fault codes from various control modules (BCM, BMS, etc.) that a generic OBD-II scanner cannot access. They can also monitor live data during a 'no-start' event if it can be replicated.
  • Detailed Description: Provide the service center with as much detail as possible: when it happens, how long it's dead, what you do to get it working again, and any other symptoms. This helps them narrow down the cause.
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